Subcutaneous infusion device for injecting medicinal substances

ABSTRACT

A medical delivery device is provided for delivering a medicinal substance into a user&#39;s body. A foldable hub has a left wing and a right wing, where the hub is attached at one end to a tube, and at an opposite end to a needle. At least one first rib is disposed on the left wing and at least one second rib is disposed on the right wing. When the wings are folded back away from the needle and pinched together, the first and second ribs prevent twisting and/or sliding of the wings relative to each other during an insertion of the needle into a user&#39;s skin, thereby preventing a breakage of the needle due to undesirable movement of the wings.

CROSS REFERENCE

The present application is a 35 U.S.C. § 371 National Stage applicationwhich claims priority to International Application No. PCT/US2015/022494filed on Mar. 25, 2015 under 35 U.S.C. §§ 119(a) and 365(b), whichclaims priority to a U.S. provisional patent application Ser. No.61/971,966 filed on Mar. 28, 2014 under 35 U.S.C. § 119(e); both ofwhich applications are incorporated herein by reference.

BACKGROUND

The present disclosure generally relates to devices for injectingmedicinal substances, and more particularly relates to a medical fluiddelivery device for subcutaneously administering viscous liquidmedicines into the body of a user.

Subcutaneous infusion devices are well known in the medical arts for usein the administration of a selected medicinal substance to a desiredinfusion site located underneath the skin of a patient or user. Commonlyincluded in such infusion device is a tubular cannula or catheter thatis supported by and protrudes from a hub for receiving the medicinalsubstance via a delivery tubing. Typically, the hub includes a smallneedle that is inserted just under the surface of the skin, and remainsin place for up to several days.

More specifically, such infusion devices provide an alternative tointravenous delivery of medicines and allow the medicinal substance tobe administered through a layer of skin immediately below the dermis andepidermis. As is known in the art, such use of the subcutaneous infusiondevices decreases the number of times the patient must have an injectionto receive frequently administered medicines. Although not all medicinescan be administered through such infusion devices, they are an effectiveand convenient way to administer medicinal substances without having toimpose multiple injections on the patient.

However, some medicinal substances are highly viscous (i.e., in therange of 3-10 cP or centipoise) and are delivered at high flow rates,and conventional subcutaneous infusion devices are not designed todeliver the highly viscous substance at these flow rates. As a result, abuild-up of excessive delivery pressure during the delivery of suchsubstances is likely to occur, and clogging may occur in the needle orits adjacent areas during infusion. Further, because the needle used inthe infusion device is typically bent about 90 degrees, the risk ofkinking is relatively high at or near the bent portion of the needle.

Another issue of conventional infusion devices is that movement of thehub can cause the needle to break during use. Foldable gripping wingsare typically attached to the hub for securely holding the needle wheninserting the needle straight into the desired infusion site at a 90degree angle relative to the skin surface. Specifically, the wings arefolded back away from the needle and pinched together between twofingers. At times, the folded wings slide against each other during theinsertion step, making the insertion of the needle rather challenging.Further, if the needle is made of a smaller diameter, the needle is notsupported firmly and causes it to break during use.

Therefore, there is a need for improving subcutaneous infusion devicesto facilitate a more stable retention of the needle on the skin duringthe insertion step, and for reducing flow resistance of highly viscoussubstance during the delivery step.

SUMMARY

The present disclosure is directed to a medical fluid delivery devicefor subcutaneously administering viscous liquid medicines into the bodyof a user or patient. The present infusion device is designed to reducea pressure drop (or flow resistance) that occurs during the deliverystep of the viscous liquid or solution into a subcutaneous space of theuser's skin. As described in further detail below, the present infusiondevice delivers the viscous liquid at a higher flow rate than theconventional devices due to the geometry of a hub and a needle.

One aspect of the present infusion device is that low flow resistance isachieved for high viscosity liquids (e.g., 3-20 cP) in flow ratesranging 40 to 400 ml/hr (or milliliter/hour) during subcutaneousdelivery. Specifically, a 24G (or gauge) needle having a thin tubularwall is provided for accommodating the viscous liquid, and a mid-regionof the needle is slightly bent at a predetermined radius of curvature,such that the mid-region surrounds a support region located at an outerend of the hub.

Another important aspect is that the present infusion device providessecure placement of the needle that reduces disturbance to the desiredinfusion site, and enhances comfort during infusion. A plurality ofsubstantially diagonally disposed ribs is provided on a bottom side ofthe hub for preventing unwanted movement of the hub while worn by theuser. More specifically, the diagonal bottom ribs are angled in such amanner that a forward movement toward the sharp end of the needle isprevented while a backward movement away from the sharp end of theneedle is allowed. Furthermore, the diagonal pattern also stabilizes thehub for lateral disturbances after installation of the needle. Thisarrangement reduces shear and/or normal stress on the bent portion ofthe needle.

Yet another aspect of the present device is that a top side of the hubincludes at least two ribs, each one of which is respectively located ona left wing and a right wing of the hub. Each rib is asymmetricallydisposed on the wings, such that when the wings are folded back awayfrom the needle and pinched together, the two ribs prevent twistingand/or sliding of the wings relative to each other during an insertionof the needle into the skin. Accordingly, the needle remains stable andstraight during the insertion, preventing a breakage of the needle dueto undesirable movement of the wings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a top perspective view of the present infusion devicefeaturing a winged hub having top ribs;

FIG. 2 is a vertical cross-section taken along the line 2-2 of FIG. 1and in the direction generally indicated;

FIG. 3 is a top view of the present hub featuring angled bottom ribs;

FIG. 4 is a vertical cross-section taken along the line 4-4 of FIG. 3and in the direction generally indicated;

FIG. 5 is a front view of the winged hub folded away from a needle inpreparation of an insertion of the needle into an infusion site;

FIG. 6 is a perspective view of the present infusion device beinginserted into the infusion site;

FIG. 7 is a perspective view of the present infusion device duringinfusion; and

FIG. 8 is an enlarged perspective view of the winged hub after theneedle is inserted into the infusion site.

DETAILED DESCRIPTION

Referring now to FIGS. 1-2, the present subcutaneous infusion device isgenerally designated 10 and is designed for subcutaneously delivering amedicinal substance below the dermis and epidermis. An exemplarymedicinal substance may include nutritional products and Chinese herbalmedicinal products. It is contemplated that the device 10 is disposable.Included in the device 10 is a luer cap 12 configured for receiving theliquid at one end, and at an opposite end, is attached to a female luerconnector 14 using complementary helically threaded portions forthreadably fastening the cap and connector together. For carrying aviscous liquid medicine to an infusion site, a flexible elongated tube16 is attached at one end to the female luer connector 14, and at anopposite end to a foldable hub 18 having a left or first wing 20 and aright or second wing 22.

An exemplary length of the tube 16 is approximately 24 inches, but it isalso contemplated that any length of tube can be utilized to suitdifferent applications. Regulating a flow of the viscous liquid medicinein the tube 16 is achieved by transversely adjusting a slide clamp 24relative to a longitudinal axis of the tube. As an example, a movablerelease slot 26 is provided in a center of the slide clamp 24 such thatthe clamp can transition between an occluding position and anon-occluding position by selectively sliding the release slot relativeto the tube 16.

In a preferred embodiment, the winged hub 18 is molded, as by injectionmolding or the like, such that the hub and its connecting elements areintegrally formed. However, it is also contemplated that the hub 18 isattachable to the connecting elements by chemical adhesives, solventboding, ultrasonic welding or other conventional fastening techniques.More specifically, the hub 18 is attached at one end to the tube 16, andat an opposite end to a needle 28, which is slidably fitted into andsafeguarded by a needle protector 30 when not in use. It is contemplatedthat after the hub 18 is molded, the needle 28 is assembled onto the hub18 using an adhesive. Alternatively, the hub 18 may be over-molded overthe needle 28.

An exemplary needle size is approximately 24G for ensuring comfortduring infusion, and an exemplary needle length may be one of 6, 9, or12 mm (or millimeter) depending on an application. Preferably, theneedle 28 has a thin tubular wall for accommodating the viscous liquidmedicine.

An important aspect of the present hub 18 is that each of the foldableleft and right wings 20, 22 of the hub has at least one top rib 32, 34extending along an entire longitudinal length of a corresponding wing.Each top rib 32, 34 is disposed on an upper surface 36 of thecorresponding wing 20, 22, such that when the wings are folded, the topribs 32, 34 are directly in contact with the upper surface 36 of acorresponding opposite wing. As a result, the top rib 32 disposed on theleft wing 20 engages the upper surface 36 of the right wing 22, andconversely the top rib 34 disposed on the right wing 22 engages theupper surface 36 of the left wing 20.

As illustrated in an exemplary FIGS. 1 and 5 embodiment, a left or firsttop rib 32 is asymmetrically disposed from a right or second top rib 34such that the first top rib 32 is juxtaposed with the second top rib 34when the wings 20, 22 are folded back away from the needle 28 andpinched together (FIG. 5). More specifically, the first top rib 32 isspaced in parallel from an elongated center section 38 of the hub 18 ata first predetermined distance D_(A) (FIG. 1), but the second top rib 34is spaced in parallel from the center section at a second predetermineddistance D_(B) (FIG. 1), where the first distance D_(A) is differentfrom the second distance D_(B).

For example, as best shown in the FIG. 5 embodiment, the first distanceD_(A) is longer than the second distance D_(B), and the first rib 32goes over the second rib 34 such that the ribs 32, 34 are adjacentlypositioned with each other when the wings 20, 22 are folded back. As aresult, this particular configuration of the top ribs 32, 34 preventsthe wings 20, 22 from twisting or sliding relative to each other,thereby reducing the risk of breakage of the needle 28 during theinsertion of the needle into the skin.

Returning now to FIGS. 1-2, a first insertion opening 40 at a first endof the center section 38 is configured for accommodating insertion ofthe needle 28, and a second insertion opening 42 at a second oppositeend of the center section in fluid communication with the tube 16 isconfigured for accommodating insertion of the tube. In a preferredembodiment, the tube 16 is inserted into the first insertion opening 40approximately half a length of the center section 38 to reduce a totallength of the needle 28 (FIG. 2).

Both openings 40, 42 provide a passage way for the delivery of theliquid medicine. This passage way provides low flow resistance for highviscosity liquids (e.g., 3-20 cP) in flow rates ranging 40 to 400 ml/hrduring subcutaneous delivery without dropping a fluid pressure more than10 psi (or pounds per square inch). More specifically, an exemplary 24Gstainless needle 28 having the thin tubular wall is configured foraccommodating the viscous liquid medicine, and a mid-region 44 of theneedle 28 is slightly bent at a predetermined radius of curvature (e.g.,0.125″ typically and not less than 0.060″ or more than 0.200″), suchthat the mid-region of the needle surrounds a support region 46 locatedat or near the first insertion opening 40 of the center section 38.

It is preferred that the mid-region 44 of the needle 28 is bentgradually at an angle of 45 to 90 degrees (nominally close to 90degrees), such that the support region 46 buttresses against the bentmid-region of the needle. A sharp end of the needle 28 extends outwardlyfrom the first insertion opening 40 of the center section 38 so that thesharp end of the needle is disposed transverse to a longitudinal axis ofthe center section. Consequently, the support region 46 reduces the riskof needle breakage, and provides integrated support for the bentmid-region 44 not only during the insertion of the needle 28 into theskin but also while being attached to the user's body.

Referring now to FIGS. 2-4 and 8, a plurality of substantiallydiagonally disposed bottom ribs 48 a, 48 b is provided on a lower orbottom surface 50 of each wing 20, 22 for preventing unwanted movementof the hub 18 during use. It is preferred that the bottom ribs 48 a, 48b are generally evenly spaced in parallel, and extend along a fulldiagonal length of a corresponding wing 20, 22. The bottom ribs 48 a, 48b are angled or slanted in such a manner that a forward movement towardthe sharp end of the needle 28 is prevented, while a backward movementaway from the sharp end of the needle is allowed. This particulararrangement reduces shear and/or normal stress on the bent mid-region 44of the needle 28 during use.

In a preferred embodiment, both the first and second wings 20, 22 of thehub 18 have the bottom ribs 48 a, 48 b positioned on the lower surface50 at an angle of approximately 45 degrees relative to the longitudinalaxis of the center section 38. An important aspect of the ribs 48 a, 48b is, however, that each bottom rib 48 a disposed on the lower surface50 of the first wing 20 is inclined or sloped upwardly from a left sideof the first wing to a right side of the first wing toward the centersection 38. In a mirrored orientation, each bottom rib 48 b disposed onthe lower surface 50 of the second wing 22 is declined or slopeddownwardly from a left side of the second wing adjacent the centersection 38 to a right side of the second wing. As a whole, the bottomribs 48 a, 48 b are constructed and arranged in a chevron or herringbonepattern, thereby preventing unwanted movement of the hub 18 while beingattached to the user's body.

This enhanced friction provided by the ribs 48 a, 48 b prevents slippageof the hub 18 from the skin during use. While diagonally arranged ribs48 a, 48 b are shown for illustration purposes, any type of knurling ortextured ribs, ridges, grooves, or bumps are contemplated fordisposition as a friction formation on the lower surface 50 of the wings20, 22 for enhancing friction in this manner. Further, the angularorientation and/or spacing of the ribs 48 a, 48 b is variable to suitthe situation.

Referring now to FIGS. 5-7, an exemplary use of the present infusiondevice is illustrated in greater detail. Before inserting the needle 28into the skin, the user folds the wings 20, 22 back away from the needle28 and pinches the wings together between two fingers. Then, the usersubsequently removes the needle protector 30 from the needle 28, anddiscards the protector (FIG. 5). In preparation of the insertion, theuser pinches an inch of the cleansed skin at the desired infusion site,and inserts the needle 28 with a darting motion, straight into theinfusion site at a 90 degree angle (FIG. 6). Next, the user checks aneedle placement with a syringe 52 by pulling a plunger 54 backward. Ifblood is seen in the syringe 52, then the present device 10 is removedand discarded in case of a disposable device. Otherwise, the userrepeats the process of preparing the present device 10 and the infusionsite. If no blood is seen in the syringe 52, the user secures the needle28 in place, and starts infusion as directed by a healthcareprofessional (FIGS. 7-8).

While a particular embodiment of the present infusion device has beenshown and described, it will be appreciated by those skilled in the artthat changes and modifications may be made thereto without departingfrom the present disclosure in its broader aspects and as set forth inthe following claims.

1-16. (canceled)
 17. A subcutaneous infusion device, comprising: afoldable hub having a left wing and a right wing, the hub beingconfigured to receive a tube at a first end, wherein a bottom surface ofeach of the left wing and right wing is configured to be placed incontact with a user's skin; a support region disposed at a second end ofthe hub opposite the first end; and a needle attached to the hub,wherein the needle includes a first portion and a second portion,wherein the first portion and second portion are connected by amid-region of the needle, the mid-region being bent at a predeterminedradius of curvature, such that the mid-region surrounds the supportregion.
 18. The infusion device of claim 17, wherein the mid-region ofthe needle is bent at an angle of 45 to 90 degrees, such that thesupport region buttresses against the bent mid-region of the needle. 19.(canceled)
 20. The infusion device of claim 17, wherein the secondportion of the needle includes a sharp end of the needle extendingoutwardly from the mid-region of the needle so that the sharp end of theneedle is disposed transverse to a longitudinal axis of the hub.
 21. Theinfusion device of claim 20, wherein the sharp end is perpendicular tothe longitudinal axis of the hub, and wherein the second portion isstraight.
 22. The infusion device of claim 17, wherein the bottomsurface of each of the left wing and right wing includes a ribconfigured to be placed in contact with the user's skin to preventunwanted movement of the hub during use.
 23. The infusion device ofclaim 17, wherein the hub terminates at the first portion of the needle.24. The infusion device of claim 17, wherein the hub is configured toreceive the tube approximately halfway into a longitudinal length of acenter section of the infusion device, wherein the center sectionincludes the hub and the support region.
 25. The infusion device ofclaim 17, wherein the needle extends through the second end of the hub.26. A subcutaneous infusion device, comprising: a foldable hub having aleft wing and a right wing, the hub being configured to receive a tubeat a first end; a support region disposed at a second end of the hubopposite the first end; and a needle attached to the hub, wherein theneedle includes a first portion and a second portion, the second portionincluding a sharp end of the needle, wherein the first portion andsecond portion are connected by a mid-region of the needle, themid-region being bent at a predetermined radius of curvature, such thatthe mid-region surrounds the support region, and wherein the hubterminates at the first portion of the needle.
 27. The infusion deviceof claim 26, wherein the mid-region of the needle is bent at an angle of45 to 90 degrees, such that the support region buttresses against thebent mid-region of the needle.
 28. The infusion device of claim 26,wherein the second portion of the needle includes a sharp end of theneedle extending outwardly from the mid-region of the needle so that thesharp end of the needle is disposed transverse to a longitudinal axis ofthe hub.
 29. The infusion device of claim 28, wherein the sharp end isperpendicular to the longitudinal axis of the hub, and wherein thesecond portion is straight.
 30. The infusion device of claim 26, whereina bottom surface of each of the left wing and right wing includes a ribconfigured to be placed in contact with the user's skin to preventunwanted movement of the hub during use.
 31. The infusion device ofclaim 26, wherein the hub is configured to receive the tubeapproximately halfway into a longitudinal length of a center section ofthe infusion device, wherein the center section includes the hub and thesupport region.
 32. A subcutaneous infusion device, comprising: a centersection including: a foldable hub having a left wing and a right wing,and a support region disposed at a second end of the hub opposite thefirst end; a tube inserted into a first end of the hub approximatelyhalfway into a longitudinal length of the center section; and a needleattached to the hub, wherein the needle includes a first portion and asecond portion, wherein the first portion and second portion areconnected by a mid-region of the needle, the mid-region being bent at apredetermined radius of curvature, such that the mid-region surroundsthe support region.
 33. The infusion device of claim 32, wherein themid-region of the needle is bent at an angle of 45 to 90 degrees, suchthat the support region buttresses against the bent mid-region of theneedle.
 34. The infusion device of claim 32, wherein the second portionof the needle includes a sharp end of the needle extending outwardlyfrom the mid-region of the needle so that the sharp end of the needle isdisposed transverse to a longitudinal axis of the hub.
 35. The infusiondevice of claim 34, wherein the sharp end is perpendicular to thelongitudinal axis of the hub, and wherein the second portion isstraight.
 36. The infusion device of claim 32, wherein a bottom surfaceof each of the left wing and right wing includes a rib configured to beplaced in contact with the user's skin to prevent unwanted movement ofthe hub during use.
 37. The infusion device of claim 32, wherein firstportion and mid-region of the needle have a longitudinal lengthapproximately half the length of the center section.
 38. The infusiondevice of claim 32, wherein the first end includes a first insertionopening accommodating the tube, and wherein the second end includes asecond insertion opening accommodating the first portion of the needle.